Review on CLOUDREAM Gamecube Controller Adapter for Super Smash Bros Switch, Wii U, Switch, and PC. Turbo and Vibration Support. No Lag & Driver-Free Gamecube Adapter by Montez Vazquez

Bought while waiting for Smash Ultimate for Switch. I confirm it works great. There's a slight lag, but that's to be expected even from an official Nintendo adapter. Any adapter that converts GameCube controllers to USB will have a slight lag. This does not make it unplayable or even noticeable in most cases. I've used this with 4 GameCube controllers on the Ultimate and it works like a charm. It comes with black USB and gray USB. The black USB is the only one you need to make it work. The gray USB is for vibration only. I don't like it, so I just connect black. It also works with Wii U and PC. It also works great with the Dolphin emulator on PC!